Projection apparatus.



A. AMES, In. PROJECTION APPARATUS. APPLICATION FILED SEPT. 30. mil

' Patented Feb. 20,1917.-

2 SHEETS-SHEET I. a

acZehkri/ A. AMES, 1R. PROJECTION APPARATUS.

APPLICATION FILED SEPT. 30, HHS.

Patented F011 20, 1917.

2 SHEETS-SHE 2.

/ #9 I IL'g 6,

fm -miw waerfi awcea 1 22i? @Zibrneya:

ADELBERT AMES, JIL, OF TEWKSBURY, MASSACHUSETTS.

PROJECTION APPARATUS.

Specification of Letters Patent.

Patented Feb. 20, 1917.

Application filed September 30, 1916. Serial No. 123,175.

To all 207mm it may concern:

Be it known that I, ADELBERT Alan's, J r., a citizen of the United States, and resident of Tewksbury, inthe county of Middlesex and State of Massachusetts, have invented new and useful Improvements in Projection Apparatus, of which the following is a specification. f V

This invention relates to light projection apparatus designed to project a concentrated beam of light which is sharply and regularly defined on at least one side. More particularly-the invention relates to a headlight for use on automobiles and the like, adapted to illuminate the roadway far in advance of a vehicle without producing 'upward glare, that is, without projecting substantially any light above a horizontal plane passing through the region of the light source and at the same time adapted to produce distributed illumination for relatively short and intermediate distances along the roadway. I

In my prior applications Sr. No. 72,503, Sr. No. 72,504: and Sr. No. 72,505, all filed January 17, 1916, and Sr. No. 102,085, Sr. No. 102,086 and Sr. No. 102,087 all filed June 0, 1916, I have'disclosed certain types of headlights designed to project a beam of light of the kind above mentioned. Apparatus of one of these typescomprises a reflector having a paraboloidal reflecting surface on one side of a horizontal plane through the light source, and having an ellipsoidal, hyperboloidal or other reflecting surface on the other side of the horizontal plane, the first surface being adapted to project a concentrated beam of light along and below the horizontal plane for illuminating distant portions of the roadway, and the other reflecting surface being to project a divergent beam of light to near and intermediate portions ofthe roadway. This type of headlight can be employed with the paraboloidal surface either below or above the horizontal plane but it is preferably employed with the paraboloidal surface below the horizontal plane and with an ellipsoidal surface above the horizontal plane.

Apparatus of another of these types comprises a paraboloidal or other reflecting surface adapted to project a concentrated beam of light, the reflecting surface being positioned on one side of a horizontal plane through the region of the light source, and a deflector positioned on the the horizontal plane in such manner as to deflect light to the reflector so as to be pro jected in and below the horizontal plane. This type of reflector may likewise be employed with the paraboloidal surface either above or below the horizontal plane, but it is preferably employed in the latter position.

The apparatus of the various types have in common, among other features, a reflecting surface on at least one side of a horizontal plane containing the axis of the surface which is adapted and arranged to project a concentrated beam of light along and below the horizontal plane without projecting substantially any lightupwardly. This reflectingsurface preferably has the con tour of a'paraboloid of revolution, but any paraboloidal or other surface which is adapted to the purpose'may' be employed. When this surface is below the horizontal plane containing its axis the light source is positioned rearwardly of the focus and when the surface is above the horizontal plane the light source is positioned forwardly of'the focus; and in either event the light source is preferably positioned above the horizontal plane in such manner that no light strikes the surface at such angles as to be reflected upwardly.

The causes of upward glare in headlights of these types as well as certain means for eliminating such upward glare have been described at length in the applications above referred to, and reference is herebymade to those applications, particularly Sr. No. 102,085 and Sr. No. 102,086, for a more detailed description of the underlying principles involved.

The principal object of this invention is to eliminate upward glare in headlights of the types described, and at the same time to utilize all or substantially all of the reother side of fleeting surfaces for projecting a concentrated beam of light in substantially an axial direction, whereby a beam of light may be produced which is sharply and regularly defined on its upper side, that is, which has a light degree of concentration just within the boundary of its upper side and which has substantially no light without the boundary and whose boundary on its upper side is regular, that is, whose boundary contains substantially no irregularities.

Another object of the invention is to provide means whereby a standard incandescent headlightlamp may be employed in headlights of the types described and in such manner that the greatest degree of concentration in the central upper portion of the sharply defined beam may be obtained, whereby distant portions of the roadway may be more thoroughly illuminated.

Another object of the invention is to provide means for universally adjusting the lamp bulb in such manner that it may be accurately positioned with respect to the focus or foci of the reflector. This preferably includes means for adjusting the lamp along its own axis, along the axis of the reflector, and transversely to the axis of the reflector.

Another object of the invention is to provide means for hermetically sealing the re fleeting surface of the reflector so as to exclude the atmosphere whereby the tarnishing effects and reduced reflecting power of the reflecting surface due to the action of the atmosphere are eliminated.

I also preferably provide hermetic sealing means of such character that the light source is accessible for adjustment, replacement, etc, without disturbing the sealing means. In the preferred form of this phase of the invention a transparent globe'is positioned between the light source and the reflecting source in such manner that the small amount of light which may be reflected from the surface of the globe facing the light source is not reflected, either directly or indirectly, to the paraboloidal reflecting surface at such angles as to be projected upwardly. With the paraboloidal surface below the light source this involves placing the center of the globe in front of the light source, the light source being positioned behind the focus of the reflector; and with the paraboloidal reflecting surface above the horizontal plane through the light source the center of the globe is positioned behind the light source, the light source being positioned in front of the focus. This feature of the invention is particularly applicable is connection with a deflector on the side of the horizontal plane opposite the paraboloidal reflector, and when using a deflector the center thereof is positioned on the side of the light source opposite the focus of the paraboloidal reflector. When the reflector is below the horizontal plane through the light source the center of the spherical deflector is positioned behind the light source.

In the accompanying drawings,

Figure 1 is a vertical longitudinal section of a compound reflector having the axis of the lamp bulb arranged obliquely with respect to the axis of the reflector;

Fig. 2 is a front view of the apparatus shown in Fig. 1;

Fig. 3 is a vertical longitudinal section of a. modified form of compound reflector together with a special form of lamp bulb;

Fig. 4t is a front view of the apparatus shown in Fig. 3;

Fig. 5 is a diagram showing the compound reflector in inverted position and showing the light source suitably positioned in front of the focus of the pa'raboloidal reflector;

Fig. 6 is a vertical longitudinal section of the type of apparatus having a deflector;

Fig. 7 is a plan view of the apparatus shown in Fig. 6 with the cover removed; and

Fig. 8 is a vertical longitudinal section of apparatus similar to that shown in Fig. 5, but having the light source mounted in front of the deflector.

I have illustrated this invention as embodied in a number of different types and styles of projection apparatus, the various types having in common, as above stated, on at least one side of a horizontal plane containing the axis of the reflector, a paraboloidal or other reflecting surface adapted to project a concentrated beam of light along the axis, for illuminating distant portions of the .roadway. In Figs. 1 and 2, for example, the paraboloidal reflecting surface P is positioned below the axis and an ellipsoidal reflector E is positioned above the axis for reflecting a divergent beam of light to nearer portions of the roadway the two portions being joined together by a horizontal member.

With apparatus having the reflecting surface which is adapted to project a concentrated beam along its axis positioned below the horizontal plane containing its axis, a light source, which has substantial dimensions and which cannot therefore be placed substantially wholly in the focus, must be positioned above the horizontal axial plane and behind the transverse plane passing through the focus of the reflecting surface through the lowermost forward point of the reflecting surface, if it is desired to have no light strike the reflecting surface at such angles as to be reflected upwardly and yet utilize all the reflecting surface. Referring to Fig. 1, for example, the light source must lie wholly above the horizontal plane of the paraboloidal reflector P and wholly behind 1 which joins-the a plane,

. of thelight source j which it is permlsslble'to place source is limited as above described, Iv .it highlyadvantageous ,:to employa coni-J flected from-theinner surface of thelamp 'fbulb so ,asto form. a. virtual image at coinciding, 3 5

"got the focusfand so-that the lies along I or behind the above ainentione'd transverseplane." In Figs. l,l3,'-'f6-andf8,

f surfaceflof-'thebulblwill pass in the'jre'ar'of thefocusjfand therefore boloidal reflector invention 1 j v adj usting the lamp in; such. manner that a filamentof; the character described can ment of the" invention 'illustrated','j the i ad 'justinglmean's comprises a lamp; socket fisioblique; to the axis 'vided with flat, lateral focusof reflector P and the lowermost forward point 4. v

If the light source extends below the horizontal plane,'.,light from the portions extending below the plane will be reflected upwardly from the portions of the reflectoradjacent the horizontal-plane, as-fully ex-- plainedxin my prior application 'Sr. No.

102,085, filed June 6,1916. =If the light 'Sourceextends in front of: the-transverse; light from the forward portions ofthe source willstrike' the forward portions- I of the reflecting surfaceas if co ning 15 from in front of the fdcus landv will there reflected upwardly. Consequently, the light source is preferably positioned above and behind these respective planes.

Furthermore,

degree of intensity of that portion of the beam just below for illuminating distant portions of the roadway, it is necessary topositi'on as much i in close proximity to'the focus as possible.

cal light-source, a"V-shaped light source,

a light source-having'bne V-shaped 'fila- I V-shaped f "filament in a 'plane'perpendicular thereto,j

- the apexes-and axes of the "two filaments I Qr-.indeed "any light source which has one or; more V-shaped sections,"

ment in a 'verticalfplaneand one and to position the light source with its apex 1n thefocus, so that the lower side of' the filament'liesalong'the axis in the rear. garn r edge have illustrated 1 us of the most common typeset-"light sources of the {character described, viz., a Vs-shaped incandescent fila- Inent and in Fig. I- have illustrated an other type, viz., the conical ty'pepcompris- Fing a-spiral filament 5 of uniformly varying According-Jtd'one of the objects-of this provide .Ineans for universally lamp having a properlyfposition ed with respectffto the-fllfo adapted to receive the ferrule 7'of "the'lan ip bulb 8 and having its axis of the reflector,-

tal member '1'.

cannot onlybe adjusted forwardly and "vided in the upper whereby the lamp' ore be trated as having its the light source,-the second focusiof this reflector being positioned in front of the v preferably'in or below theaxis in order to obtain a high the axis of the reflector,,

'Where the region ht I 'nd his axially f displaced paraboloidal reflector is belowsaid horizontal plane .lamp bulb 8 andjforwa'rd In Figs. 3 andA-Ixhz'tvd "other embodiment of'my invention. comsuch as-istshown and deprisinga reflector I [scribed in' my application Slr. ,No 102,085,

axis obliquejto the h s t Pm-E. earsl9 having*slots 11 therein: to rece'1ve bolts 12, whichi arefl adapted to secure the socket to the 'horizon- The slots are made some 'what wider than the bolts so that the socket it. may be mountedi'i Inas inuch asone jlegf along" the axi'sjfof .the bulb, the apex of the filament" maybe-positionedgin the focus f :of' the; paraboloidal U lower leg ?of the' filament 'will be disposed rearwardly along the axisof the reflector but it can also be adjusted laterally with re A set screw 13 is prospectto the axis.

portion of thesocket 6 forsecuring the lamp in adjusted position, may also be adjusted along its own axis. These three different adjustments render the lamp bulb universally adjustable so that the light source can be suitably positioned even though the filament is not concentrically mounted with respect tothe axis of the bulb or is otherwise inaccurately mounted.

The ellipsoidal reflecting surface is'illus- I focus 6 in the rear of focus e. and of the 'paraboloidal reflector P. 'However,

the POSltlQIl of the'ellipsoidal reflector E maybe varied, depending.upon'the'distribution of light throughout, near and intermediate ."portions I desired,- as fully plication Sr." No. 102,085.

of the roadway which is discussed 'in my prior apvWith a substantially spherical jlampi ulb such as is commonly employed, I ave found that a substantial amount of-light is re- 'the light source if the light source'is at the center of the bulb, or if thelight source from the center of the bulb side of the center. Therefore, when the thefilight source 2 the axis" of the yf of the center small amount of ffromf i the inner is preferably disposed alon of. the hulb, so that the light which is reflected striirej in such m IlIustrated'Fan and: comprising-- a specially constructed not be;.fmounted;in ;sucli manner'fthat its axis n-F-Jthe; ordinary 'way. of the filament lies reflector P, and the along. .the axisof j the reflector in the rear of the focus as in Fig.1. By rotating the the image is formed on the. opposite the afore- V shaped filament 14, .one 'legjof;.which .isvdisposed alongthe axis of he amp. instead of-being disposed .on one id fjthe 'a-xisjm symmetry withithe other leg. With this arrangement the damp-"need e Pe lamp the other leg oflthe filament may be positioned above 1 the horizontal plane through the focus in such manner that all the light incident to the paraboloidal reflector P will be projected in and below a horizontal direction. The ellipsoidal reflector E is preferabl positioned with its focus e in the rear of the light source.

In this embodiment the h light source is also preferably. positioned in front of the center of the lamp bulb so that light reflected from the upper half of the bulb will pass in the rear of the focus f and hence be rojected downwardly. rom the ner surface of the lower-half of thela'mp bulb 16 will likewise passin the i rear of the light source but will not be reflected upwardly from the ellipsoidal reflector E, if the foc'us'e of the ellipsoidaljre- I the lower half H loidal.

tioned wholly in-front of a transverse plane D The rear upper edge of the parabodownwardly. When flector is positioned far'enough in the rear of the light source, or if the forward focus of the ellipsoidal reflectoris not positioned too far in front'of the rearward focus 6.

In Fig. 5 I have illustrated one-effective disposition of the light source in a reflector, of: which is hyperboloidal and the upper half P of which is parabo- The light source 17 must be posipassing through the line 18 joining the forward central point 19 of'theparaboloidal.

reflector with the focus f of this reflector, in order that all light emanating upwardly w ll strike the reflector P. as if coming from 1n front of the focus fand thereby be reflected the V-shaped filament is mounted by means back of the focus, as in Figs. 1 and 4, the filament is preferably positioned with its lower leg in the axis and with the rear end of the lower leg in the focus. The hyperboloidal reflector H is'so shaped and is so positioned with respect to the light source that the light reflected therefrom 1n directed to the form of a divergent beam is the near and intermediate portions of the roadway according to the desired distribution of this portion of the illumination.

The apparatus 'illustrated'in Figs. 6 and loidal reflector P and loidal reflector P is provided with a flat extension member 22 lying substantially inthe horizontalplane containing the axis of the reflector. provided in substantially the same plane to serve as a cover for the paraboloidal reflector and also as a support for the deflector, main lamp and auxiliary lamp A The member 23 is secured to the upper edge of the paraboloidal reflector in any suitable manner which will provide a hermetically tight joint between the two members. The forward edge 24 of the member 23 is curved upwardly at right angles to form a rib for The "light reflected A flat member 23 is preferably- Washers flanges 24 and 27, angular member 28 and the glass cover to afford. an air-tight connection.

The spherical deflector D is preferably positioned withits center d; in the rear of the focus 7, of the paraboloidal reflector P The means for supportlng the deflector comprises a flat member 31 brazed or otherwise secured to the outer surface of the spherical deflector, the member 31 havinglongitudinal slots'coiiperating with bolts 32 passing.

through the member 23. Thus, the deflector maybe adjusted along the axis of the reflector in guides-33 so as to'suitably position the center of the deflector with respect to the focus of the reflector.

The lamp is mounted in a socket 34 with its axis oblique to the axis of the reflector, and means similar to the means shown in Figs. 1 and 2 is provided for adjusting the lamp socket along and transversely with respect to the axis, the rear lower portion of ,the deflector D being cut away to receive the lamp. A set screw 36 is provided to hold the lamp in ad- A substantlally clrcular opening is provided inv the member 23 to receive the lamp. bulb and to justed position. in the socket.

permit the light which is deflected from the deflector to pass downwardly t0 the reflect on.. 1 q

An opemng 37i's'provided-in the extension the axis of the reflector- 22 to receivethe wires 38 which pass in A through the insulating conduit 39 to the aux- 1l1ary light source A. A cover 0 is suitably secured to the edges of the members 22 and 23 to inclose the upper portion of the apparatus. 1 I

In this embodimentof the invention the light source is preferablypositioned between the focus f of the reflector'P and the center cl, of the deflector D with the apex of the filament in the focus andthe lower leg extending rearwardly along the axis of the re-.

flector. -Thus, all light radiating flown-g .wardly from the source is reflected in and below a horizontal direction and the light which radiates-upwardly from the source is deflected downwardly, passing behind thecenter (1 and thence behind the focus f, and thence to the reflector in such manneras to be reflected downwardly. By varying the position of the center d along the axis of thereflector in the rear of the light source,

the desired distribution of light to near .and

intermediate portions of the roadway may be secured. The light source is preferably positioned in front of the center of the lamp bulb so that no light will be reflected from the interior surface of the upper half of the bulb to the reflector in such manner as to be projected upwardly, as described in connection with F igs. 1 and 4.

This type of reflector may, if desired, be used in a position. inverted with respect to that shown in Fig. 6 in which case the light source must be positioned in front of the focus, as illustrated in Fig. 5, and the center of the spherical deflector should be positioned in front of the light source. Further-' more, the center of the spherical bulb should be positioned on the same side of the light source as the center of the spherical deflector, that is, in front of the light source. This inverted arrangement of the apparatus is not preferred, however, for the reason that some light emanates forwardly and upwardly directly through the front transparent cover of the apparatus in such manner as to produce a slight upward glare. On the other hand, if the apparatus is in the position shown in Fig. 6 this light which radiates directly out tirough the front cover strikes the roadway in front of the vehicle and is therefore utilized to advantage. Another advantage in using the-apparatus in the position illustrated is that the sharply defined upper edge of the beam is substantially flat, whereas with the apparatus inverted the upper side of the beam, while sharply defined, has a conical contour and the amount of light immediately below the horizontal plane through the light source rapidly falls off from the center of the beam laterally.

The embodiment illustrated in Fig. 8 is similar to that shown in Figs. 6 and 7 and comprises a lower paraboloidal reflector P, and a spherical deflector D,. However, instead of the lamp bulb being mounted behind the deflector on the extension 22, it is mounted in front of the deflector on the horizontal member 23, means for adjusting the lamp along its own axis, along the axis of the reflector and laterally with respect to the axis of the reflector being provided as in Figs. 1, '2, 6 and 7. lVith this arrangement the lower side of the light source is preferably positioned in the axis of the reflector behind the focus in such manner that the forward ends of the filament do not project in front of a transverse plane through the line 41 connecting the focus with the lower central point of the reflector.

In Fig. 8 I have also illustrated another feature of my invention, namely, means for hermetically sealing the reflecting surface of the paraboloidal reflector from the outside atmosphere in such manner that the light source is accessible for adjustment and replacement Without disturbing the sealing means. The particular embodiment of this feature illustrated in the figure comprises a glass globe 42 between the lamp bulb and the reflector. The glass globe is positioned with its center 0 in front of the light source and in front of the center-cl of the deflector-D The globe is held in this position by means of a flange 43 extending entirely around the upper edge of the globe and beingdisposed in a horizontal plane. A flange 44 is provided on the rear upper edge of the reflector P to cooperate with the flange 43 not be hermetically sealed to the apparatus.

With the transparent globe 42 positioned with its center in front of the light source and in front of the center (Z, of the deflector 1),, all light which is reflected to the deflector D, from the interior surface of the lower half of the globe passes upwardly in front of the center (Z, of the deflector, so that it is deflected downwardly to the reflector P in such manner as to pass behind the focus 7", and therefore is projected downwardly. While the disposition of the center of the deflector and the center of the sealing globe do not have to be as shown, it is essential that the light radiating upwardly from the source be deflected to the reflector to pass downwardly behind the focus, and it is also essential that the light reflected from the inner surface of the globe 42 pass upwardly to the deflector in such manner as to be deflected to the reflector so as to pass downwardly behind the focus of the reflector, since any light incident to the reflector as if coming from in front of the focus would be projected upwardly.

With the lamp bulb mounted in front of the deflector the apparatus is rendered more compact and at the same time the lamp bulb is accessible from the front for adjustment and repairs which, in many instances, is more convenient. Fu1."thermore, the sealing means is so arranged that the lamp bulb and spherical deflector are accessible without disturbing the sealing means. Thus, the reflecting surface of P may be sealed immediately after polishing, and by excluding the'atmosphere and by avoiding the contact of perspiration, grease and other foreign matter with the surface during the process of repairing or adjusting the lamp, the reflecting surface may be maintained at its maximum reflecting efficiency for an indefinite period.

By Virtue of the improvements of this application, the concentrated horizontal beam of light is not only sharply defined on its upper side, but it is also regularly defined on its upper side. If a beam of light be projected upon a vertical wall at a distance of to 100 feet, the upper edge of the illuminated zone will have substantially no irregularities. On the other hand, the upper edge will either comprise a straight horizontal line, a smooth curve having its highest point in the middle of the beam and gradually declining on either side, or a substantially V-shaped outline, the apex of the V lying at the axis of the reflector and the legs lying slightly below the horizontal plane containing the axis. The precise outline of the upperside of the beam depends upon the relative adjustment of the parts and can be regulated to meet various conditions. For example, where little, if any, light is required on either side of the roadway the V- shaped outline may be employed resulting in a somewhat greater concentration of light along the roadway. Conversely, where a beam of light extending laterally somewhat on either side of the roadway is required, as at present in some places by law, the apparatus may be adjusted to produce a beam of light, the upper side of which is defined by substantially a horizontal plane, the central portion of the beam being more intense, however, for adequately illuminating distant portions of the roadway.

It is to be noted that the words horizontal, vertical, upward, downward, etc, are used throughout the specification and claims merely for convenience in referring to relative locations and directions, and that my invention is not limited to headlights employed solely in the position herein described. On the contrary, the invention is applicable wherever it is desired to project a beam of light sharply defined on at least one side. I contemplate for example, applying my invention to search lights employed to illuminate buildings and the like.

I claim:

1. Projection apparatus comprising a concave reflector adapted to project a concentrated beam of light along its axis and a light source having at least two substantial dimensions, a part ofthe light source being positioned in the focus of the reflector and the other parts of the source being disposed with relation to the focus so that substantially all light incident to the reflector strikes the reflector as if coming from points axially displaced in one direction from the focus and so that a concentrated beam of light sharply and regularly defined on its upper side is projected horizontally.

2. Projection apparatus comprising a reflecting surface having substantially a con tour generated by half a revolution of a conic section, the reflecting surface being positioned on one side of a horizontal plane containing its axis in such manner that light emanating from its focus will be projected substantially horizontally, and a light source having at least two substantial dimensions, the light source being positioned with one part thereof in the focus of the reflecting surface, and the light source being positioned substantially wholly above said plane in such manner that substantially no light will be reflected upwardly.

3. Projection apparatus comprising a substantially hemi-paraboloidal reflecting surface positioned below a horizontal plane containing its axis, and a light source having atleast two substantial dimensions, a part of the light source being positioned in the focus of the reflecting surface and the other parts being positioned above said horizontal plane and behind a transverse plane containing the line adjoining the focus with the lowermost central point of the reflecting surface, whereby a concentrated beam of light may be reflected in and below a horizontal direction without reflecting substantially any light upwardly.

4:. Projection apparatus comprising a concave reflector adapted to project a concentrated beam of light along its axis, a light source a part of which is positioned in the focus of the reflecting surface and the other parts of which are so disposed with relation to the focus that light therefrom strikes the reflector as if coming from points axially displaced in one direction from the focus and so that said concentrated beam of light is sharply and regularly defined on its upper side, and adjusting means whereby the light source may be placed and maintained in the said position.

5. Projection apparatus comprising a substantially hemi-paraboloidal reflecting surface positioned below a horizontal plane containing its axis, a light source having at least two substantial dimensions, a part of the light source being positioned in the focus of the reflecting surface and the other parts being positioned above said horizontal plane and behind a vertical transverse plane so as to reflect a concentrated beam of light in and below a horizontal direction without reflecting substantially any light upwardly, and means whereby the light source may be adjusted along the axis of the reflecting surface.

6. Projection apparatus comprising a concave reflector adapted and arranged to project a concentrated beam of light along and below a horizontal plane, a light source having at least two substantial dimensions, a part of the light source being positioned in the focus of the reflector and the other parts of the source being disposed with relation to the focus so that light therefrom strikes the reflector as if coming from points axially displaced in one direction from the focus and so that said concentrated beam of light is sharply and regularly defined on its upper side, and means for adjusting the light source radially with respect to the axis of the reflector.

7. Projection apparatus comprising a con cave reflector adapted and arranged to project a concentrated beam of light along and below a horizontal plane, a light source having at least two substantial dimensions, a part of the light source being positioned in the focus of the reflector and the other parts of the source being disposed with relation to the focus so that light therefrom strikes the reflector as if coming from points axially displaced in one direction from the focus and so that said concentrated beam of light is sharply and regularly defined on its upper side, and universal adjusting means whereby the light source may be adjusted with respect to the focus of the reflector.

8. Projection apparatus comprising a re fleeting surface having substantially a contour generated by half a revolution of a conic section, the reflecting surface being positioned on one side of a horizontal plane containing its axis in such manner that light emanating from its focus will be projected substantially horizontally, and a light source having a Vshaped section, a part of the light source being disposed in the focus of the reflecting surface and the other parts of the light source being disposed with respect to the focus so that said concentrated beam of light is sharply and regularly defined on its upper side.

9. Projection apparatus comprising a concave reflector, a lamp bulb mounted with its axis oblique to the axis of the reflector, and a filament within the lamp bulb having a V-shaped section, a. part of the filament being in the focus of the reflector and one side of the filament being disposed along said axis.

10. Projection apparatus comprising a concave reflector, a lamp bulb mounted with its axis oblique to the axis of the reflector, and a filament within the lamp bulb having a V-shaped section the apex of which lies substantially in the focus of the reflector and the lower side of which is disposed along said axis.

11. Projection apparatus comprising a substantially hemi-paraboloidal reflecting surface positioned on one side of a horizontal plane containing its axis, and a light source having a il-shaped section, the light source being positioned with its apex substantially in the focus of the reflecting surface, one side of the source being disposed along said axis on that side of said focus from which light incident to the reflecting surface will be reflected along and below said horizontal plane, the other portions of the source being so disposed that the light therefrom incident to the reflecting surface will be reflected downwardly.

12. Projection apparatus comprising a substantially henii paraboloidal reflecting surface positioned below a horizontal plane containing its axis, and a light source having a V-shaped section, the light source being positioned with its apex substantially in the focus of the reflecting surface, one side of the source being disposed along said axis rearwardly of said focus, and the other portion of the source being disposed above said plane and rearwardly of a vertical transverse plane through said focus.

13. Projection apparatus comprising a concave reflector, a lamp bulb mounted with its axis oblique to the axis of the reflector, a filament within the lamp bulb having a V-shaped filament and having a part thereof in the focus of the reflector and having the lower side thereof substantially in said axis, and means whereby the lamp bulb may be adjusted along its axis.

14E. Projection apparatus comprising a concave reflector, a lamp bulb mounted with its axis oblique to the axis of the reflector, a filament within the lamp bulb having a V-shaped section and having a part thereof in the focus of the reflector and having the lower side thereof substantially in said axis, andmeans whereby the lamp bulb'may be adjusted along said axis.

15. Projection apparatus comprising a concave reflector, a lamp bulb mounted with its axis oblique to the axis of the reflector, a filament within the lamp bulb having a V-shaped section and having a part thereof in the focus of the reflector and having the lower side thereof substantially in said axis, and means whereby the lamp may be radially adjusted with respect to said axis.

16. Projection apparatus comprising a concave reflector, a lamp bulb mounted with its axis oblique to the axis of the reflector, a filament within the lamp bulb having a V-shaped section and having a part thereof in the focus of the reflector and having the lower leg thereof substantially in said axis, and universal adjusting means whereby the lamp bulb may be adjusted with respect to said focus. I

17. Projection apparatus comprising a substantially paraboloidal reflector, a substantially spherical deflector positioned with its center in the region of the focus of the reflector, a lamp bulb, a light source within the lamp bulb and in said region, and means for mounting the lamp bulb forwardly of said focus.

18. Projection apparatus comprising a substantially hemi-paraboloidal reflecting surface positioned below a horizontal plane containing its axis, a substantially spherical deflector positioned above said plane, a lamp bulb, a light source within the lamp bulb, the center of the deflector and the light source being position in the region of the focus of the reflecting surface, and means in front of said focus and at least partially above said plane for supporting the lamp bulb.

19. Projection apparatus comprising a substantially hemi-paraboloidal reflector positioned below a horizontal plane containing its axis, a substantially flat member attached to the upper side 'of the reflector, a spherical deflector mounted on the upper side of said member with its center in the region of the focus of the reflector, and a lamp bulb mounted on said member in front of said focus with its light source in said region.

20. Projection apparatus comprising a substantially hemi-paraboloidal reflector positioned below a horizontal plane containing its axis, a substantially flat member attached to the upper edge of the reflector, a spherical deflector mounted on the upper side of said member with its center in the region of the focus of the reflector, a lamp bulb mounted on said member in front of said focus with its axis oblique to said plane, and a V-shaped filament within the lamp bulb, a part of the filament being positioned in said focus and the lower leg of the filament being disposed along the axis of the reflector.

21. Projection apparatus comprising a reflecting surface, a light source positioned in the region of the focus of the reflecting surface, and means for hermetically sealing the reflecting surface in such manner that the light source is accessible for adjustment and replacement without disturbing the sealing means.

22. Projection apparatus comprising a reflecting surface, a light source positioned in the region of the focus of the reflecting surface, and means for hermetically sealing the reflecting surface in such manner that the light source is accessible without disturbing the sealing means, the sealing means including a transparent tween the light source and the reflecting surface.

23. Projection apparatus comprising a reflecting surface, a light source positioned in the region of the focus of the reflecting surface, and means for hermetically sealing the reflecting surface in such manner that the light source is accessible without disturbing the sealing means, the sealing means including a transparent member positioned between the light source and the reflecting surface and shaped so that no light is reflected from the inner surface of the transparent member to the reflecting surface at such angles asto be projected upwardly 24. Light projection apparatus comprismember interposed be ing a reflector, a lamp bulb, a light source within the lamp bulb, the lamp bulb being positioned with the light source in the region of the focus of the reflector, a transparent front cover hermetically sealed to the reflector, and a transparent globe partially surrounding the lamp bulb, the globe being hermetically sealed to the reflector in such manner as wholly to seal the reflecting surface of the reflector from the atmosphere and as to render the light source accessible Without disturbing the sealing means.

25. Projection apparatus comprising a substantially hemi-paraboloidal reflecting surface positioned on one side of a horizontal plane containing its axis, a light source positioned in the region of the focus of the reflecting surface, a deflector on the other side of said plane for deflecting light to the reflecting surface and means for her metically sealing the reflecting surface including a transparent globe between the light source and the reflecting surface, the light source and deflector being positioned with respect to each other and with respect to the focus of the reflecting surface so that a concentrated beam of light-may be projected along said plane without projecting substantially any light upwardly, and the globe being so shaped and positioned with respect to the light source and deflector that substantially no light is reflected therefrom to the deflector at such angles as to be deflected to the reflecting surface in such manner as to be projected upwardly.

26. Projection apparatus comprising a substantially hemi -paraboloidal reflecting surface positioned on one side of a horizontal plane containing its axis, a light source mounted above said plane and in the region of the focus of the reflecting surface, a transparent member between the light source and the reflecting surface, and means to hermetically seal the transparent member to the reflecting surface.

27. Projection apparatus comprising a substantially hemi-paraboloidal reflector positioned on one side of a horizontal plane containing its axis, a. transparent front cover hermetically sealed to the reflector, a member substantially in said plane hermetically sealed to the horizontal edge of the reflector, a light source mounted on the said member, transparent means between the reflector and light source, the transparent means being hermetically sealed to the said member, whereby the reflecting surface of the reflector is wholly sealed from the atmosphere and the light source is accessible without disturbing the sealing means.

28. Projection apparatus comprising a substantially hemi-paraboloidal reflector on one side of a plane containing its axis, a substantially spherical deflector on the other side of said plane having its center displaced from the focus of therefiector along said axis, a light source positioned between transverse planes through said center and said focus, respectively, and a substantially spherical transparent globe between the light source and reflector for hermetically sealing the reflecting surface of the reflector, the center of the globe being positioned on the same side of the transverse plane 10 through said center as the light source.

Signed by me at Boston, Massachusetts, this twenty-second day of September 1916.

ADELBERT AMES, JR.

Copies 01' this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

